A California based optical networking company asked ATS for thermal management services to manage excess heat in a telecom cabinet.
The OEM’s optical transport board employed 16 heat sinks, two of which were ATS maxiFLOWTM heat sinks. These were attached to hot processors using the ATS maxiGRIPTM clip system. The other heat sinks were all 15mm x 15mm straight fin designs attached to various semiconductors using a thermally conductive epoxy. The thermal epoxy was meant to provide a secure, mechanical bond for mounting the heat sinks to the ICs on their circuit board. But the results were not as expected. The epoxy-attached heat sinks began falling off the PCBs in both field and lab deployments.
The customer’s team considered alternative approaches, including thermal adhesive tape but were unable to find a suitable solution. ATS was brought onto the team to find the problems root cause and provide a suitable solution that met the OEMs technical requirements and cost constraints.
ATS analyzed the customer’s circuit boards, heat sinks, and the thermal epoxy, and completed thermal modeling and analysis of the application. Following this approach, ATS recommended using the originally designed-in heat sinks. The thermal analysis showed their performance was satisfactory, with margin, for this application. ATS recommended a heat sink clip be used instead of thermal epoxy. The ATS superGRIPTM heat sink clip and a phase change thermal interface material were then introduced.
ATS supplied early samples of a standard superGRIP and 15mm x 15mm straight fin heat sink. After physical testing, both thermal teams came to the conclusion that the new solution would improve both the mechanical attachment and thermal performance. However, the standard off the shelf superGRIP was not the right dimensions for a best fit; critical to it’s mechanical attachment and capability to apply the right amount of pressure for phase change material to be effective. That correct amount of pressure is critical to phase change material so it can give the best heat transfer from the semiconductor to the heat sink.
ATS developed a custom superGRIP for the application, and upon further testing found the combination of straight fin heat sink, superGRIP, and phase change interface to meet the design requirements.
The result of this partnering work between ATS and their customer were:
- Reduced cost of production as epoxy required more training to use and had a shelf life
- Passing of NEBS shock and vibration testing
- Increased product MTBF and reliability
- The OEM was able to ship their product to gain sales
If your team is facing a similar dilemma, contact us at ATS ; Phone: 781-769-2800, email: sales.hq@qats.com or visit our web site at http://www.qats.com. You can also click to ATS’s You Tube Channel to see a demo of our superGRIP heat sink clip